Meningitis

Question 1

Hib vaccination had a profound population-wide effect in all-age incidence of H. influenzae meningitis reducing it by _____% between 1986 and 2007 to a near elimination level.

Answer 1

97%

Question 2

1) The meninges are made up of three separate membranes, which are what?
2) Meningitis refers to inflammation of what?

Answer 2

1) Dura mater, arachnoid, and pia mater
2) The subarachnoid space or spinal fluid

Question 3

The ependymal cells of the choroid plexus function as a ____________ system to form the blood-CSF barrier

Answer 3

active-transport

Question 4

CNS bacterial pathogens produce an extensive polysaccharide capsule resistant to neutrophil phagocytosis and __________________ ________________.

Answer 4

complement opsonization.

Question 5

The development of bacterial meningitis involves four main processes, list them

Answer 5

1) Mucosal colonization
2) Bacteria in SA space
3) ^ ICP
4) Cerebral edema leading to neuron damage

Question 7

The effects of meningitis, namely ______________ within the subarachnoid space and the ensuing neurologic damage, are not necessarily a direct result of the pathogens themselves.

Answer 7

inflammation

Question 8

True or false: The inflammation from meningitis is not necessarily a direct result of the pathogens themselves.

Answer 8

True

Question 9

1) Vasogenic edema causes what?
2) What does this lead to?

Answer 9

1) Increased ICP
2) O2 depletion

Question 10

What 2 signs will be positive?

Answer 10

Brudzinski and Kernig’s

Question 11

1) What happens if you give abx before you get samples?
2) Should you still give abx if unable to get samples within an hour?

Answer 11

1) Sensitivity and specificity decrease
2) Yes

Question 12

True or false: Neuroimaging should not delay initiation of appropriate antibiotic therapy as doing so can result in a poor outcome in this disease.

Answer 12

True

Question 13

1) What test may be useful in differentiating between bacterial and other types of meningitis?
2) Is this test still useful if abx already given?

Answer 13

1) CSF lactate
2) Reduces sensitivity, suggesting the usefulness is compromised in those pts

Question 14

____________________________ techniques can rapidly diagnose CNS infections and may be particularly useful in patients who have received antimicrobial therapy before lumbar puncture, have negative cultures, or when the organism is fastidious or fails to grow in conventional culture.

Answer 14

Polymerase chain reaction (PCR)

Question 15

Diagnosis of tuberculous meningitis employs what?

Answer 15

Acid-fast stain, culture, and PCR of the CSF.

Question 16

1) Administration of what 3 things may be indicated for patients presenting with a possible CNS infection?
2) What else may be needed?

Answer 16

1) Fluids, electrolytes, antipyretics, and analgesics
2) Venous thromboembolism prophylaxis, antiepileptic therapy, and ICP monitoring may be needed.

Question 17

Patients may require the administration of __________ ___________ such as mannitol 25% or hypertonic 3% saline to maintain an ICP of less than 15 mm Hg (2 kPa) and a cerebral perfusion pressure of 60 mm Hg (8 kPa) or more.

Answer 17

osmotic diuretics

Question 18

In meningitis, abx penetration is increased through inflamed meninges. Why?

Answer 18

Due to:
1) damage to tight junctions between capillary endothelial cells and
2) reduction of the activity of energy-dependent efflux pumps in the choroid plexus responsible for movement of penicillins

Question 19

1) Are only ionized or nonionized antibiotics at physiologic or pathologic pH are capable of diffusion?
2) Antibiotics not extensively bound to____________ provide a larger free fraction of drug capable of passing into the CSF.

Answer 19

1) Nonionized
2) plasma proteins

Question 20

Neonates w. meningitis: What are the 2 onsets?

Answer 20

1) Early onset
Term: within 7 days
Preterm: within 72 hours
2) Community-acquired late onset
Term: > 7 days
Preterm: > 72 hours

Question 21

Define kernicterus

Answer 21

Displacement of bilirubin from albumin binding sites that cause brain damage

Question 22

What may you see the use of when treating neonate pts?

Answer 22

1) May see triple therapy
2) May see use of vancomycin

Question 23

Is gentamicin ionized or unionized?

Answer 23

Polarized (ionization); limits diffusion into CNS

Question 24

1) With vancomycin, what should you consider if Tx not working? What do you need to do regardless?
2) What is a downside of it?

Answer 24

1) Direct CNS administration; monitor serum drug levels
2) Nephro and ototoxic

Question 25

How is Macrotube minimum inhibitory concentration (MIC) determined?

Answer 25

The first clear tube read is the MIC

Question 26

1) When using Colastin, what should you consider? 2) What is recommended for **gentamicin**, tobramycin, or vancomycin use? 3) When dosing trimethoprim-sulfamathoxazole, which part do you base it on?

Answer 26

1) Intraventricular doses 2) TDM (therapeutic drug monitoring) 3) The trimethoprim

Question 27

Slide 36

Question 28

**Streptococcus pneumoniae** (Pneumococcus or Diplococcus): What things may predispose the patient to the development of pneumococcal meningitis?

Answer 28

Pneumonia, endocarditis, CSF leak secondary to head trauma, splenectomy, alcoholism, sickle cell disease, and bone-marrow transplantation

Question 29

Coma, hearing impairment, and seizures are common neurologic complications due to which kind of meningitis?

Answer 29

S. pneumoniae

Question 30

For Streptococcus pneumoniae (Pneumococcus or Diplococcus) Tx: 1) What is the empiric therapy? 2) What may substitute an abx in empiric therapy? 3) What may be used as monotherapy?

Answer 30

1) Ceftriaxone & vancomycin 2) Rifampin may be substituted for vancomycin 3) Ceftaroline may be used as monotherapy

Question 31

For Streptococcus pneumoniae (Pneumococcus or Diplococcus) meningitis Tx: 1) What is an alternative to a third-generation cephalosporin in penicillin resistant isolates? 2) Some caution is warranted with the use of ______________ for CNS infections given the risk of drug-induced seizures 3) How is this form of meningitis prevented?

Answer 31

1) Meropenem 2) imipenem 3) Vaccines

Question 32

Neisseria meningitidis (Meningococcus): 1) Incidence peaks in <_______yr(s) old; second peak in adolescents and young adults ________ to _______ years of age 2) The presence of what may be the primary clue that this is the pathogen?

Answer 32

1) <1 year old; 16 to 23 2) Petechiae

Question 33

Neisseria meningitidis (Meningococcus): 1) Empiric therapy (pre-culture)? 2) Once you get cultures back, what should you be looking to use if they're susceptible to it? 3) How is this form of meningitis prevented?

Answer 33

1) Ceftriaxone or cefotaxime 2) Penicillin G or ampicillin 3) Vaccines

Question 34

**Neisseria meningitidis:** Use meropenem for _____________ and ____________ resistant cultures

Answer 34

penicillin and cephalosporin

Question 35

**Haemophilus influenzae type b meningitis:** 1) What is the empiric therapy? 2) What is beneficial for treatment of infants and children with Hib meningitis to diminish the risk of hearing loss, if given before or concurrently with the first dose of antimicrobial agent(s)? 3) For prophylaxis, ______________ should be administered orally, once a day for 4 days (20 mg/kg/dose; maximum, 600 mg).

Answer 35

1) Ceftriaxone or cefotaxime 2) Dexamethasone 3) rifampin

Question 36

1) What should you do for prophylaxis for a person exposed to Haemophilus influenzae type b who can't take rifampin? 2) Can Haemophilus influenzae type b be prevented?

Answer 36

1) Consultation with an expert in infectious diseases is recommended; may consider ceftriaxone or cefotaxime. 2) Yes; Hib vaccine

Question 37

**Streptococcus agalactiae (Streptococcus Group B):** Recommended agents for_________________ are penicillin, ampicillin, cefazolin (if penicillin allergy and not at high risk for anaphylaxis), or vancomycin (if penicillin allergy and at high risk for anaphylaxis)

Answer 37

intrapartum prophylaxis

Question 38

**Streptococcus agalactiae (Streptococcus Group B):** Recommended agents for intrapartum prophylaxis include what?

Answer 38

1) Penicillin 2) Ampicillin 3) Cefazolin (if penicillin allergy and not at high risk for anaphylaxis) or 4) Vancomycin (if penicillin allergy and at high risk for anaphylaxis)

Question 39

**Streptococcus agalactiae (Streptococcus Group B):** 1) Empiric therapy for a newborn with early onset? 2) What abt for a newborn with late onset? 3) What abt for adults? 4) When should you use Vancomycin?

Answer 39

1) Ampicillin plus an aminoglycoside 2) Ampicillin and an aminoglycoside or cefotaxime 3) Ampicillin or penicillin G 4) Type I PCN allergy

Question 40

Listeria monocytogenes: 1) What are the empiric therapy options? 2) What is the duration of therapy?

Answer 40

1) Ampicillin or penicillin G + aminoglycoside 2) 21 days (minimum)

Question 41

Dexamethasone (steroid): 1) Associated with lower rates of what 2 sequelae in adults and children? 2) Potential concern is that adjunctive dexamethasone therapy may reduce what?

Answer 41

1) HL and short-term neurological 2) The penetration of antibiotics (i.e., vancomycin & pneumococcal meningitis caused by penicillin- or cephalosporin-resistant strains) into the CSF by inhibiting or reducing meningeal inflammation

Question 42

Dexamethasone: 1) What are the recommendations by the IDSA? 2) What is the recommendation for pneumococcal meningitis?

Answer 42

1) Call for the use of adjunctive dexamethasone in infants and children (6 weeks of age and older – may see recommendations for 2 months and older) with H. influenzae meningitis 2) Pediatrics: consider risk vs. benefit Adults: give regardless if suspected or proven

Question 43

European guidelines recommend initiating dexamethasone in all patients (adults and children) presenting with suspected or proven community-acquired bacterial meningitis and consider discontinuation only if pathogens other than __________________ or ___________________ are identified.

Answer 43

H. influenza or S. pneumoniae

Question 44

**Dexamethasone (Decadron)** 1) What is the biggest takeaway of the MOA? 2) What is are 2 common SEs? (>10%) 3) What is a less common SE (that may or may not be linked; 1-10%)? 3) List rare SEs [don't think rare ones are important] (<1%)

Answer 44

1) Anti-inflammatory 2) Hypertension, GI upset 3) Atrophic condition of skin 4) Primary adrenocortical insufficiency, Cushing syndrome, decreased body growth, increased risk of infection

Question 45

Rifampin: 1) What is the MOA? 2) What 2 things can it Tx besides meningitis? 3) What are some side effects? 4) What are some significant interactions?

Answer 45

1) Binds to the beta subunit of bacterial RNA-polymerase and inhibits transcription of DNA to RNA 2) TB and leprosy 3) Flu-like sx; rare hepatotoxicity, shock, hemolytic anemia, or acute renal failure 4) Increased risk of oral contraceptive failure via CYP450 enzyme induction; need to give HIV patients rifabutin instead (increased elimination of protease inhibitors)

Question 46

Rifampin: 1) What are 2 major downsides for female patients with the ability to reproduce? 2) What is a weird side effect?

Answer 46

1) Teratogenic + Increased risk of oral contraceptive failure via CYP450 enzyme induction 2) May turn urine and other secretions orange-red